Type: io.helidon.webclient.http2.Http2ClientProtocolConfig

Configuration options

Table 1. Optional configuration options
key type default value description

flow-control-block-timeout

Duration

PT15S

Timeout for blocking while waiting for window update when window is depleted.

initial-window-size

int

65535

Configure INITIAL_WINDOW_SIZE setting for new HTTP/2 connections. Sends to the server the size of the largest frame payload client is willing to receive. Defaults to io.helidon.http.http2.WindowSize.DEFAULT_WIN_SIZE.

max-frame-size

int

16384

Configure initial MAX_FRAME_SIZE setting for new HTTP/2 connections. Maximum size of data frames in bytes the client is prepared to accept from the server. Default value is 2^14(16_384).

max-header-list-size

long

-1

Configure initial MAX_HEADER_LIST_SIZE setting for new HTTP/2 connections. Sends to the server the maximum header field section size client is prepared to accept. Defaults to -1, which means "unconfigured".

name

string

h2

ping

boolean

false

Check healthiness of cached connections with HTTP/2.0 ping frame. Defaults to false.

ping-timeout

Duration

PT0.5S

Timeout for ping probe used for checking healthiness of cached connections. Defaults to PT0.5S, which means 500 milliseconds.

prior-knowledge

boolean

false

Prior knowledge of HTTP/2 capabilities of the server. If server we are connecting to does not support HTTP/2 and prior knowledge is set to false, only features supported by HTTP/1 will be available and attempts to use HTTP/2 specific will throw an UnsupportedOperationException.

Plain text connection

If prior knowledge is set to true, we will not attempt an upgrade of connection and use prior knowledge. If prior knowledge is set to false, we will initiate an HTTP/1 connection and upgrade it to HTTP/2, if supported by the server. plaintext connection (h2c).

TLS protected connection

If prior knowledge is set to true, we will negotiate protocol using HTTP/2 only, failing if not supported. if prior knowledge is set to false, we will negotiate protocol using both HTTP/2 and HTTP/1, using the protocol supported by server.